Fix cmake script to work on Windows

On Windows 7, installed http://www.cmake.org/files/v2.8/cmake-2.8.10.2-win32-x86.exe
When started like this: "C:\Program Files (x86)\CMake 2.8\bin\cmake.exe" .
it produced following output:

> -- Building for: Visual Studio 10
> -- The C compiler identification is MSVC 16.0.30319.1
> -- The CXX compiler identification is MSVC 16.0.30319.1
> -- Check for working C compiler using: Visual Studio 10
> -- Check for working C compiler using: Visual Studio 10 -- works
> -- Detecting C compiler ABI info
> -- Detecting C compiler ABI info - done
> -- Check for working CXX compiler using: Visual Studio 10
> -- Check for working CXX compiler using: Visual Studio 10 -- works
> -- Detecting CXX compiler ABI info
> -- Detecting CXX compiler ABI info - done
> CMake Error at src/MicroIni/CMakeLists.txt:12 (if):
>   if given arguments:
>
>     "Windows" "MATCHES" "Windows" "AND"
>
>   Unknown arguments specified
>
>
> -- Configuring incomplete, errors occurred!

It seems ${CMAKE_COMPILER_IS_GNUCXX} is not defined and if condition
fails.
Fix compilation on Visual Studio 10 Express